He has used methyl cellulose to create fried oyster stew, regularly serves custard and caviar inside eggshells and once made "chicken and dumplings" with poulet de bresse and cockscombs at the residence of the U.S. ambassador to France on national television.

But if I had to anoint one dish as chef John Besh's true signature, I'd pick what is essentially a bacon and onion pizza that everyone seems to order when they go to Luke.

The dish is called flammenkuche, and it encompasses much of what Besh aims to accomplish with his downtown brasserie.

It comes from Alsace, a region in France where the food, due to interlocking forces of geography and history, bears more than a passing resemblance to Germany's. That natural fusion -- it's evident in Alsatian wine as well -- speaks to Besh's formative training in some of both countries' better restaurants.

You can taste the overlapping influences in the flammenkuche, a quick-delicious bit of pastry work blanketed in melted Emmenthaler and fragrant of caraway.

It is also the kind of thing that goes great with beer, a quality locals had no reason to believe Besh valued until he opened Luke in the spring of 2007.

The chef rose to prominence -- first locally, then nationally -- on the strength of the controlled magic performed at Restaurant August, his elegant flagship in the shadow of the Windsor Court Hotel.

Luke is both an antidote and complement to its tonier sibling -- a lower-brow, lower-priced alternative that broadens Besh's audience while demonstrating his regular-guy taste for nonhaute cuisine.

Luke succeeds at all of this and more, including giving New Orleans a bacon cheeseburger waiters recommend with the same enthusiasm their August counterparts tout the foie gras -- and with plenty justification. (Its secret: super-smoky Allen Benton's bacon.)

The restaurant proves Besh is a chef not just of skill but range. But in its two-year existence, it has also provided vivid testimony to how difficult it can be to transition from chef to restaurateur.

Food: Very good to excellent. Luke has suckled a following with a procession of disarmingly home-spun culinary touches and broad-shouldered dishes that satisfy something more than just an appetite.

Not all of the food reaches the quality level you'd expect from someone of owner-auteur John Besh's talent, but the kitchen of executive chef Steven McHugh frequently churns out the most precise and exciting bistro cooking in New Orleans.

Ambiance: Very good. The restaurant is built into an awkward footprint on the first floor of the Hilton Hotel on St. Charles Avenue, but the most is made of it. It has benefited from a renovation of body and spirit, and the restaurant's design neatly packages its owner's complex vision.

Service: Good to very good. Service was a liability in Luke's first year of operation. It has more recently been remedied by a confident, attentive staff capable of unscripted conversation.

Luke is on the bottom floor of the Hilton Hotel on St. Charles Avenue, in the space occupied by Cobalt prior to the levee failures. It is an awkward, L-shaped footprint, two narrow, disconnected dining rooms running perpendicular into another, but the Besh team has made the best possible use of it.

The front room, equipped with broadsheet daily newspapers fixed to long sticks, conjures an era when people from all over the world converged on the Central Business District to conduct actual business.

It has benefited from a renovation of body and spirit, with Cobalt's angular, packaged modernism supplanted by a pressed tin ceiling and a masculine identity embodied by the bull's head peering from atop the bar, a tower of dark wood one can imagine Teddy Roosevelt bellying up to after slaying an elk.

Even if you're seated in the back room, where the relative sterility is erased by an open view of the glassed-in kitchen, the restaurant's design neatly packages Besh's complicated vision of a New Orleans-Alsatian brasserie partly inspired by Kolb's, the defunct downtown German restaurant that, like Luke, boasted belt-driven ceiling fans.

That is a lot of nostalgia to stuff into a single concept, not to mention one menu, and indeed Luke has not always offered a cohesive translation of its multifarious inspirations.

In its first year, I chalked-up the occasionally bizarre service, skunked mussels and pork rillettes that did little more than moisten slices of grilled bread as byproducts of doing business in a city where perfection wasn't reasonable to expect. But when the gaffes continued to mar meals in year two, it seemed clear something more problematic was afoot. How else to explain a croque madame topped with a functionally raw egg, woefully unbronzed roast chicken or a waitress taking 20 minutes to discover the Sancerre we'd ordered wasn't available?

The semi-frequent hiccups could have been the result of Besh spreading his talent pool too thin. It's also possible his diffuse ideas failed to motivate enough of the troops charged with executing them.

David Grunfeld / The Times-Picayune Luke's Stephen McHugh, executive chef and partner of the CBD restaurant located on the bottom floor of the Hilton Hotel on St. Charles Avenue.

Whatever the obstacles, in recent months Luke appears to have overcome them. Its front of the house is no longer a liability, stocked with attentive servers capable of unscripted conversation. And while not all of the food reaches the quality you'd expect from someone of Besh's talent, Luke's kitchen regularly churns out the most precise and exciting bistro cooking in New Orleans.

The restaurant's menu has always had its strengths, and executive chef Steven McHugh, who is also a partner in the business, hasn't allowed them to slip. Beyond the burger and flammenkuche, Luke has suckled a following with a procession of disarmingly home-spun touches (matzo balls simmered in cure-all chicken stock, a house salad whose buttermilk dressing alone is worth the trip downtown) and broad-shouldered dishes that satisfy something more than just an appetite.

Most notable among the latter is the cochon de lait. As a daily special on Tuesdays, a dense portion of juicy pork takes the shape and dimensions of a super-sized Rubik's Cube that arrives painted in cherry mustard and set in a cast-iron casserole with stewed, savory-sweet greens. The ingredients -- sans the greens -- are equally impressive at the center of a pressed sandwich that is offered daily with a side of Luke's house-made, textbook perfect fries.

The kitchen is at its best engaged in the primal task of coaxing the most from dark, sometimes rough flesh. Duck soaks in a vanilla bath before it's roasted to the color of chocolate, its rich gaminess further tempered by local kumquats. The choucroute -- basically the best parts of the pig, including the belly, set in a heap of sauerkraut -- is like I remembered it being in Paris, where I washed it back, just as I did at Luke, with a cold pinot gris poured into a tumbler.

And notwithstanding one unfortunate rillette episode, no one in town has a better charcuterie program than Luke. Just try the truffle-y, impossibly smooth rabbit and duck liver pate, or its textural opposite, a coarse country pate of wild boar fixed with a jewel of translucent Muscat gelee.

Oddly, considering Besh's strong identification with his Louisiana roots, Luke is most frustrating when it's taking its cues from closer to home.

The restaurant is a fine venue for slurping down raw oysters, but the company they kept on the larger seafood platters -- shell-on shrimp, crab claws, split lobster tails -- I found considerably less pristine. My excitement at seeing crawfish bisque on the menu lasted until my cup arrived containing tepid soup.

Jennifer Zdon / The Times-Picayune Chef John Besh rose to prominence -- first locally, then nationally -- on the strength of the controlled magic performed at Restaurant August, his elegant flagship in the shadow of the Windsor Court Hotel.

And there was nothing wrong with my redfish meuniere and shrimp farci (fried, stuffed shrimp) save for the fact that they were barely distinguishable from similar dishes available at lesser restaurants all over town. Either would have benefited from the level of care and imagination that went into the black forest pot de creme, basically chocolate cake reimagined as custard embedded with brandied cherries, each one a boozy, mouth-filling explosion waiting to happen.

Dessert was not a forum where Luke regularly shined, but that pot de creme came on my last visit, and together with the gateau basque -- dense but moist vanilla cake pelted with fresh strawberries and a poof of creme fraiche -- opened up the possibility that a weakness could become a strength.

Luke is almost the great brasserie Besh imagined. On the evidence of the foundation already laid, I wouldn't bet against it getting there soon.